A team led by researchers at California Institute of Technology has detected a Neptune-sized exoplanet orbiting a young star about 500 light years away from Earth.

The planet, dubbed as K2-33b, is the youngest fully-developed exoplanet discovered so far. Researchers believe that it is only about 5 to 10 million years, which is considered to be an infant in cosmic scale. On the other hand, the Earth is roughly 4.5 billion years old.

According to a paper published in the journal Nature, K2-33b was first detected using NASA's Kepler space telescope during its K2 mission using transit method, which uses the dimming of the light emitted of a host star to determine the presence of a planet. The existence of the K2-33b was validated by the W.M. Keck Observatory in Hawaii.

"This discovery is a remarkable milestone in exoplanet science," said Erik Petigura, a postdoctoral scholar in planetary science and a coauthor on the paper, in a statement. "The newborn planet K2-33b will help us understand how planets form, which is important for understanding the processes that led to the formation of the earth and eventually the origin of life."

The super-Neptune planet is five times the size of earth and only takes 5.4 days to orbit around its host star K2-33. Observations from NASA's space telescope revealed that K2-33 has a small amount of disk material left, suggesting that the star is in its final planet-forming stages.

The discovery of the planet may make or break the migration theory. Migration theory states that large planets were formed far from their host star and migrate inwards overtime. However, K2-33b is so close to its parent star in its early ages, suggesting that if migration occurs, it might happen quickly. It is also possible that giant planets can in fact be formed near their star, debunking the migration theory.

Although K2-33b is already fully formed, researchers believe that it will still evolve over time. The researchers are now planning to determine the mass and density of the planet in order to have a better understanding of the planet's fate later in life.